I’ve done a couple of posts on tafoni, the exotic and wonderful natural sculpturing of, commonly, sandstones. As I was putting together the piece on the ways in which Gaudi was inspired by natural forms, I came across photographs of the spectacular tafoni in the El Corte de Madera Creek Open Space Preserve in the Santa Cruz Mountains south of San Mateo, and I later realised how easy it would be to incorporate this into the itinerary for our final day wandering around the ever-alluring state of California. A little more than a mile hike through the woods brings you to the outcrop (having taken careful notice of the instructions on what to do when confronted by a mountain lion – I particularly liked the advice that, if necessary, you should “fight back”). Then there it is amid the trees, a great rounded knob of the thirty million year old Vaqueros Sandstone, the unevenly distributed calcium carbonate cement stimulating the natural processes of weathering to create their art, exploiting the softer, less cemented sandstone beneath the outer crust; there is a viewing platform and a very well put-together explanation. The tafoni are extraordinary and diverse – I shall simply leave the photos to speak for themselves.